Solderless coaxial connectors

ABSTRACT

Solderless plug and union connectors for coaxial shielded cables, having a body member provided with a prong or alternately a union junction contacting the stripped end of the inner conductor bent in the form of a loop disposed in a transverse plane, the prong being electrically insulated from the remainder of the body which is electrically connected to the outer tubular braided conductor of the cable having its end clamped between a dielectric washer and a shoulder portion of a hollow sleeve member mechanically and electrically connected to the connector body.

United States Patent Inventor James W. Shirey Lakeland, Mich.

Aug. 28, 1968 Apr. 6, 1971 John Schroeder Howell, Mich.

a fractional part interest Continuation-in-part of application Ser. No. 673,852, Oct. 9, 1967, now abandoned.

Appl. No. Filed Patented Assignee SOLDERLESS COAXIAL CONNECTORS 2,449,983 9/1948 Devol 174/88.2 2,552,313 5/1951 Friedberg et al 174/19 2,896,186 7/1959 Hardmark 339/100 3,184,706 5/1965 Atkins 339/177 FOREIGN PATENTS 1,251,099 12/1960 France 339/177 1,300,612 6/1962 France 339/177 925,840 3/1955 Germany 339/177 Primary Examiner-Marvin A. Champion Assistant ExaminerJoseph H. McGlynn Att0rney--Hauke, Gifford and Patalidis ABSTRACT: Solderless plug and union connectors for coaxial shielded cables, having a body member provided with a prong or alternately a union junction contacting the stripped end of the inner conductor bent in the form of a loop disposed in a transverse plane, the prong being electrically insulated from the remainder of the body which is electrically connected to the outer tubular braided conductor of the cable having its end clamped between a dielectric washer and a shoulder portion of a hollow sleeve member mechanically and electrically connected to the connector body.

Patented April & 1911 V 3,573,712

2 Sheets-Shed 1 "tall"! am FIG-3 32 V 3a 5 5'4 film 24 INVENTOR Z6 Z8 7 44 amass w. SHIREY BY m, m, #4, fl w ATTORNEYS Patented April 6, 1971 FIG.7

u/ W/S /2 6% FIGS h I /0 66 99 26 h 44 v v 22 74 2a 76 86 20 9/ do IG. IO

INVENTOR JAMES w. SHIREY ATTORNEYS SOLDERLESS COAXIAL CONNECTORS CROSS-REFERENCE TO RELATED APPLICATION The present application is a continuation-in-part of application Ser. No. 673,852, filed Oct. 9, 1967, and now abandoned.

BACKGROUND OF THE INVENTION The present invention relates to the broad field of electrical connectors and more particularly to improved connectors for use with flexible coaxial cables of the type consisting of an inner central conductor, of solid or stranded current conductive metal wire, covered by a cylindrical layer of dielectric material, such dielectric beingin turn covered by a cylindrical tubular metallic braid which forms the outer conductor of the cable. The outer. tubular conductor is generally in turn covered with a cylindrical layer of insulation, made of a material having in addition good mechanical and weather resistant properties.

Such coaxial cables are used very extensively today for connection between an aerial for propagation or reception of high frequency radio waves and the input of a radio receiver or the output of a radio transmitter. Connectors are available for connecting coaxial cables to the aerial terminals or to the radio apparatus terminals, or, by way of a double-ended union junction, for connecting separate lengths of coaxial cables. Such connectors include a body portion having a hollow prong into which the inner conductor of the coaxial cable is introduced and crimped or soldered; the outer tubular braided connector, after removal of a portion of the outermost insulating covering, is provided with means for either clamping such outer conductor in electrical contact therewith or for soldering the outer braided conductor to the connector body.

The soldered and/or crimped connections effectuate both the electrical connection and the mechanical securing of the coaxial cable in appropriate position when the connector is attached by means of a threaded ring or collar member to the externally threaded surface of an appropriate receptacle for the prong. Such an arrangement, as available in the previous art, has many inconveniences as it requires, for mounting of the connector upon the end of a coaxial cable, the availability of a soldering iron and a certain degree of skill on the part of the person attaching the connector upon the end of the cable. Additionally, in view of the heat required for properly soldering the inner conductor to the hollow prong and the outer tubular braided conductor to the connector sleeve, heat damage may affect the insulating quality of the dielectrics in the cable and in the connector, and such soldered connections do not generally effectuate good mechanical connections. Where crimping is used to effectuate electrical and mechanical connection between the conductors of the cable, such as the inner conductor and a portion of the connector such as the hollow prong, special tools are required, and the crimping operation has a tendency to stress the materials and reduce their normal tensile strength.

SUMMARY OF THE INVENTION The present invention has for its principal object to provide a coaxial cable connector having substantially all the advantages of the prior art connectors with respect to weatherproofing and clamping of the tubular braided conductor, while providing means whereby the inner conductor is firmly clamped and anchored in an appropriate axial position and in electrical contact with the connector prong.

Another object of the present invention is to provide a coaxial connector wherein the mechanical and electrical connections respectively between the inner conductor of a coaxial cable and the prong of the connector or a union junction and between the outer tubular braided conductor of the cable and the body of the connector, are effected by way of rigid mechanical clamping means, without resorting to soldering of the diverse conductors with the appropriate portions of the connector.

Still another object of the present invention is to provide a solderless coaxial connector construction having all the structural and electrical advantages of soldered connectors, which permits to effectuate strong mechanical and electrical c0nnections with a coaxial cable, which only requires the use of simple and easily available tools such as a pocket knife and a pair of pliers at most, which is simple to manufacture with a few parts of simple configuration and which may be made in any appropriate type of material permitting strong mechanical connections and adequate lossless electrical connections.

Other objects and advantages of the present invention will be apparent to those skilled in the art from the detailed description hereinafter of a few examples of embodiments thereof, when such description is read in conjunction with the attached drawings wherein like numerals refer to like or equivalent parts and in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a partial longitudinal sectional view of a typical coaxial cable, with an end thereof properly dressed previously to attaching thereto a coaxial prong connector according to an example of the present invention, with parts of such connector already passed over the cable;

FIG. 2 is a view similar to FIG. 1, but showing all the elements of the connector of the invention in position with respect to the coaxial cable just before appropriate clamping of the connector body to said cable;

FIG. 3 is a partial end view from line 3-3 of FIG. 2;

FIG. 4 is an exploded view of the plug portion of a connector according to the present invention;

FIG. 5 is a longitudinal sectional view of the connector according to the present invention attached to the end of a typical coaxial cable;

FIG. 6 is a longitudinal section of a connector according to the present invention shown mounted upon an appropriate input or output receptacle;

FIGS. 7 and 8 are views similar to FIGS. 5 and 6 but showing a modification of the invention;

FIG. 9 is an elevation view of an example of coaxial cable solderless union connector according to the present invention; and

FIG. 10 is a sectional view along line 10-10 of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings and more particularly to FIG. 1 thereof, a typical coaxial cable 10 comprises an inner conductor 12 made of a solid wire or, alternately, made of stranded wire of an electrically conductive metal such as copper or the like, surrounded by a cylindrical layer 14 of dielectric material such as polyethane or Teflon, or the like, which is in turn surrounded by a cylindrical tubular metallic braid 16, forming the outer conductor of the cable. The outer tubular braided conductor 16 is generally in turn surrounded by a tubular or sleevelike covering 18 of a weather resistant material such as a rubber or a polyvinyl plastic.

Typical of such coaxial cable are RG/U 58 coaxial cable having an outer diameter of 0.208 inch, RG/U 59, having an outer diameter of 0.255 inches, etc.

Preparatory to attaching the connector of the invention at the end of coaxial cable 10, the cable is dressed by removing the outer covering 18 from approximately 16inch from the end of the cable, as shown at the right-hand side of FIG. 1. The outer tubular braided conductor 16 and the inner dielectric layer 14 are cut off at about A inch from the end of the cable, such that, as shown, about V4 inch of the center inner conductor 12 is exposed and about 7/32 to kinch of the outer tubular braided conductor 16 is exposed, as shown. A hollow metallic sleeve member 20 and a metallic collar member 22, fonning part of the connector of the invention, are threaded over the cable 10, as shown.

As illustrated in FlG. 2, a metallic washer 24 is subsequently disposed over the exposed tubular braided conductor 16, the end of the tubular braided conductor 16 being subsequently pushed back or radially fanned out as shown at 26, thus exposing portion of the inner dielectric layer 14. A dielectric insulator washer 28 is then inserted over the inner dielectric layer 14 on the end of the cable in such a manner that the fanned out end portion 26 of tubular braided conductor 16 is disposed radially between the metallic washer 24 and the insulator washer 28. The exposed end of inner conductor 12 is subsequently bent and formed, as shown best in FIGS. 2 and 3, in a small radius loop 30 disposed in a transverse plane, the looped end 30 of the inner wire 12 slightly overlapping the edge of hole 32 in the center of the insulator overlapping the edge of hole washer 28 so as to cause an interference preventing the insulator washer 28 from slipping off the end of the inner dielectric layer 14.

The connector, according to the present invention, further includes a plugvmember 34, shown in detail in the exploded view of FIG. 4 as comprising a hollow body member 36 provided with a longitudinally disposed bore 38 having an enlarged overcut portion40. The periphery of the rearward portion of hollow body member 36 is threaded as shown at 42 and the forward portion thereof forms an enlarged diameter shoulder portion 44. An insulating sleeve 46 has a reduced outer diameter portion 48 adapted to be press fitted within the longitudinal bore 38 in body member 36 and an outer enlarged diameter portion 50 adapted to be press fitted within the enlarged bore portion 40 of body member 36. The inner longitudinal bore portion 52 of the insulating sleeve 46 is adapted to receive, under press fit, the body portion 54 of a prong 56 having an enlarged shoulder rearward portion 58 adapted to engage the enlarged inner diameter bore portion 60 of insulating sleeve 46 and forming an anterior electrical contact and mechanical clamping surface 62 for the purpose to be hereinafter explained in detail. The prong 56 is thus electrically insulated from the hollow body member 36, and prong 56, insulating sleeve 46 and hollow body member 36 form in assembly a plug 34, as shown in H05. 3 and 5, the peripheral surface of the enlarged shoulder portion 44 thereof being preferably provided with a knurled surface as shown at 65 in FIG. 2.

Once the coaxial cable is prepared in the manner shown in FIG. 2, all that is required to finish the assembly of the connector of the invention on the end of the cable is to screwplug member 34 into hollow sleeve member by engaging the thread 42 of the plug with the inner thread 64 on the internal bore 66 of the forward end of the hollow sleeve member 20. The hollow sleeve member 20 has a reduced diameter bore 68 adapted to engage the peripheral surface of insulating covering 18 of the cable and defining an innner annular transverse abutment surface 70. When plug member 34 is tightly screwed into hollow sleeve member 20, as shown in FIG. 5, the bent over looped end 30 of the inner conductor 12 is thus tightly secured by being clamped between the rearward end surface 62 of prong 56 and the forward surface of dielectric washer 28, thus affording a continuous electric path from the inner conductor 12 to the prong 56, while, at the same time, a strong mechanical and electrical connection is effected between the hollow sleeve member 20 and the outer braided conductor 16, by way of annular abutment surface 70 being tightly engaged with the metallic washer 24 having an edge projecting beyond the periphery of the tubular dielectric covering 18, the fanned out upturned end portion 26 of the braided conductor 16 being securely clamped between the metallic washer 24 and the dielectric washer 28.

The collar member 22 has an internal bore 72 provided with an internal thread 74 proximate the forward end thereof, and is formed with a rearwardly disposed inwardly extending shoulder portion 76 adapted to engage the rearward surface of the shoulder portion 44 of plug member 34, when the connector is used to securely fasten the plug member with the prong 56 inserted in the usual manner in the recess 78 of a receptacle 80 forming the terminal of the equipment, not shown, to which cable 10 is electrically connected. Recess78 is insulated by means such as, for example, an insulating sleeve 82 from the body of the receptacle 80 and the peripheral surface thereof is provided with a thread 84 adapted to engage the thread 74 within the collar member 22. In this manner, a solid mechanical attachment of cable 10 is accomplished by means of the connector of the invention, while a continuous electrical path is effected from the inner conductor 12 to the recess 78 of the receptacle and from the outer tubular braided conductor 16 to the body 80 of the receptacle.

In order to facilitate manipulation of the conductor of the invention, a portion of the peripheral surface of the collar member 22 is preferably provided with a knurled surface as shown at 86 in F IG. 1, and a portion of the rearward end of hollow sleeve member 20 is also provided with a knurled surface as shown at 88 in FIG. 1. Knurled surface 88 on hollow sleeve member 20 causes an expansion of the metal where such knurled surface is formed which in turn causes an increase of diameter of the hollow sleeve, as shown at 90 in FIGS. 2, 5 and 6, or alternately, the hollow sleeve member may be provided with a slightly enlarged rear end portion 90 of a diameter slightly larger than the inner reduced diameter bore 91 formed by the shoulder portion 76 of the collar member 22.

Referring now to FIGS. 7 and 8, there is shown a modification of a coaxial cable plug connector according to the present invention, which is substantially alike the connector of FIGS. 16 provided with substantial simplification of the construction and the mounting thereof on the end of a coaxial cable. The metallic washer is omitted and the metallic tubular braid 16 is directly clamped at its fanned out end 26 between the insulating washer 28 and the shouldered or annular abutment surface 70 of the hollow sleeve member 20. The plug member 34 is substantially simplified by using a hollow body member 36 made of dielectric material and having on the periphery thereof a thread 42 adapted to engage the inner thread 64 on the internal bore of the forward end of the hollow sleeve member 20. The end of the hollow sleeve member 20 abutting against the annular portion 44 of the plug body 34 is provided with an outwardly tapering or shoulder portion 86 such as to form an adequate mechanical and electrical connection with the inner annular surface of the inwardly radially projecting shoulder portion 76 of the collar member 22. Preferably,.the inner surface of the longitudinal bore 68 in the hollow sleeve member 20 is provided with a thread as shown at 89 and is of a diameter such as to firmly grip the outer surface of the resilient outer covering 18 of the coaxial cable 10 such as to provide improved mechanical holding and weather proofing of the connector assembly.

As shown in FIGS. 910, the principles of the present invention may be adapted to a coaxial cable solderless union connector for connecting together separate ends of coaxial cables 10. Such connector is substantially alike the plug connector of FIGS. 78, and obviously may also be made alike the example of connector of HG. l-6, with the collar member 22 being omitted, and the full connector includes a pair of hollow sleeve members 20, the mechanical and electrical interconnection between the pair of hollow sleeve members being effected by means of a union junction generally designated at 92. As shown in detail in FIG. 10, the union junction 92 includes a metallic hollow body member 93, having a peripheral thread at both ends thereof as shown at 94 for engagement with the internal thread 64 on the end of the inner bore of each sleeve member 20. The hollow body member 93 is provided with an enlarged diameter portion 96 having preferably a knurl, as shown at 98, on the peripheral surface thereof. Within the hollow body member 93 is disposed an elongated current conductive junction rod member 100 provided with an enlarged diameter portion 102 on each end thereof, the rod member 100 being electrically insulated from the hollow body member 93 by means of a dielectric sleeve 104. ln this manner, the two lengths of coaxial cables 10 may be mechanically and electrically interconnected, after dressing the ends of the cables as previously mentioned, by tightening the two hollow sleeve members onto the union junction 92 in such manner that the bent over looped end of each inner conductor 12 is clamped securely against each enlarged end portion 102 of the junction rod member 100, the fanned out portion 26 of the cable braid 16 being, as previously mentioned, electrically connected to the hollow sleeve member 20 by being tightly engaged between the annular abutment 70 within the hollow tubular member 20 and the insulating washer 28. lf so desired, a metallic washer may be provided, as hereinbefore described, betweenthe fanned out portion of the cable braid and the annular abutment 70.

it is obvious that the structures described in the foregoing description and in the accompanying drawings is given by way of illustration only, and various changes in construction will occur to those skilled in the art, and various different modifications and embodiments may be made by those skilled in the art without departing from the scope of the invention as expressed in the following claims.

lclaim:

l. A connector for mounting on the end of a coaxial shielded cable of thetype having an inner conductor surrounded by a dielectric material in turn surrounded by an outer tubular braided conductor in turn surrounded by a dielectric material covering, said connector comprising:

an electrically conductive hollow sleeve member having a first longitudinal bore adapted to accept the coaxial cable, a second longitudinal bore of enlarged diameter provided with an internal thread and an annular abutment surface disposed between said first and second bores;

a dielectric washer disposed surrounding the dielectric material surrounding the inner conductor, the end of the tubular conductorbeing fanned out radially so as to be normally engaged between one side of said dielectric washer and said annular abutment in the hollow sleeve member, the projecting end of the inner conductor being bent over the other side of said dielectric washer;

a plug member comprising a cylindrical body and a coaxially disposed electrically conductive elongated prong member electrically insulated from said body and provided with a rearward flat surface, said body being provided with a thread on the peripheral surface thereof for engagement with the internal thread in the hollow sleeve member, the relative length of said plug member and said hollow sleeve member being such that when the plug member is threaded tight into the hollow sleeve member said inner conductor is clamped between said dielectric washer and the rearward flat surface of said current conductive elongated prong member in said plug member and said outer tubular braided conductor is clamped between said side of said dielectric washer and the annular abutment surface of said hollow sleeve member;

a forwardly disposed enlarged diameter shoulder portion on the periphery of the end of said hollow sleeve member engaging said plug member; and

a collar member having a rearwardly disposed inwardly extending shoulder portion for engagement with the enlarged diameter shoulder portion of said hollow sleeve member, said collar member having an internal thread for engagement with an external thread of a recptacle for said prong member.

2. The connector of claim 1 wherein said hollow sleeve member is provided with a knurled surface on at least a'portion of the outer surface thereof.

3. The connector of claim 1 wherein said plug member is provided with a knurled surface on the enlarged diameter por' tion thereof.

4. The connector of claim 1 wherein said collar member is provided with a knurled surface on at least a portion of the outer surface thereof.

5. The connector of claim 1 further comprising: a current conductive washer disposed around said tubular braided conductor proximate the end thereof, the fanned out portion thereof being disposed between said dielectric washer and said current conductive washer.

6. The connector of claim 1 wherein the first longitudinal bore of the hollow sleeve member has a thread thereon for improved grip upon the dielectric material covering of said coaxial cable. 

1. A connector for mounting on the end of a coaxial shielded cable of the type having an inner conductor surrounded by a dielectric material in turn surrounded by an outer tubular braided conductor in turn surrounded by a dielectric material covering, said connector comprising: an electrically conductive hollow sleeve member having a first longitudinal bore adapted to accept the coaxial cable, a second longitudinal bore of enlarged diameter provided with an internal thread and an annular abutment surface disposed between said first and second bores; a dielectric washer disposed surrounding the dielectric material surrounding the inner conductor, the end of the tubular conductor being fanned out radially so as to be normally engaged between one side of said dielectric washer and said annular abutment in the hollow sleeve member, the projecting end of the inner conductor being bent over the other side of said dielectric washer; a plug member comprising a cylindrical body and a coaxially disposed electrically conductive elongated prong member electrically insulated from said body and provided with a rearward flat surface, said body being provided with a thread on the peripheral surface thereof for engagement with the internal thread in the hollow sleeve membEr, the relative length of said plug member and said hollow sleeve member being such that when the plug member is threaded tight into the hollow sleeve member said inner conductor is clamped between said dielectric washer and the rearward flat surface of said current conductive elongated prong member in said plug member and said outer tubular braided conductor is clamped between said side of said dielectric washer and the annular abutment surface of said hollow sleeve member; a forwardly disposed enlarged diameter shoulder portion on the periphery of the end of said hollow sleeve member engaging said plug member; and a collar member having a rearwardly disposed inwardly extending shoulder portion for engagement with the enlarged diameter shoulder portion of said hollow sleeve member, said collar member having an internal thread for engagement with an external thread of a recptacle for said prong member.
 2. The connector of claim 1 wherein said hollow sleeve member is provided with a knurled surface on at least a portion of the outer surface thereof.
 3. The connector of claim 1 wherein said plug member is provided with a knurled surface on the enlarged diameter portion thereof.
 4. The connector of claim 1 wherein said collar member is provided with a knurled surface on at least a portion of the outer surface thereof.
 5. The connector of claim 1 further comprising: a current conductive washer disposed around said tubular braided conductor proximate the end thereof, the fanned out portion thereof being disposed between said dielectric washer and said current conductive washer.
 6. The connector of claim 1 wherein the first longitudinal bore of the hollow sleeve member has a thread thereon for improved grip upon the dielectric material covering of said coaxial cable. 